It was working but I covered the board in PCB lacquer for sub ambient insulation and it got into a few places it shouldn't. Physically the board seems fine - no burnt components, diagnostic LEDs come on and it goes through the usual boot cycle as you'd expect.

The CPU socket appears fine, I'm guessing the RAM slots are OK as it goes past the usual F3/F6 ram tests but I could be wrong... I'm wondering if it's the PCIe slots although they *seem* OK at a basic visual inspection.

Any ideas on how I could diagnose this or have I killed it?

Edit:
Also, forgot to add, the PCIe LEDs all light up fine depending on which slots are enabled.
And another question - what's the default positions for the I-Limit and X-Cool jumpers? I think I've got them in the right position but I'd like to be sure.

Wow, the x58 e762. I didn't know anyone still used this motherboard. I currently have it in my machine so hopefully I can help answer your last question. The default positions for both the I-limit are the bottom 2 prongs and for the x-cool left 2 prongs.

As far as the error 25 it looks like it is mainly attributed to a video card or pci-e slots. Maybe try a different video card or possibly different pci express slot.

Where was "got into a few places it shouldn't."
When you press numlock after the hang, is keyboard active?
Can you put only one memory stick in and remove the vga card and see if the same behavior/post code fail?

"few places it shouldn't" means memory slots, cpu socket, pcie slots. I know... I was stupid for assuming masking tape would work :-\

I've actually got it to boot and go into the BIOS, but it takes a few attempts. It hangs on post code 25, then I reset it (on board reset button), then it gets to 25, takes a bit longer but then keeps booting OK and will let me see the bios... however it's only really picking up the 'middle' memory channel properly and not the other two

So is there anything I can do? I've considered giving it a spray/hose down with water and then leaving it in the sun for a while, just to see if that helps but knowing my luck it'd possibly break it further x.x

Someone has offered to sell me another board so I'm considering buying that one and using liquid electrical tape. I have thought of using just eraser but I'm worried that won't be enough as this is for a 'daily use' kinda system so I'd like to keep the board safe.

Ah well... assuming it is dead it's had a good run. At one point I managed to get 10th on the 3dmark 11 Performance rankings - albeit with water cooling and some insane clocks on 4 x 480s.

what tinbo said, use a strong solvent and get something like soft wire brush to remove any residue from inside dimm slots It can be done, just requires patience. Don't use conformal or any kind of LET on motherboards or vga's, vaseline is the much better option. This is one reason why.
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